Question

Write an equation of the line in slope-intercept form which passes through (-2,0) and is perpendicular to a line whose equation is y=-3x+7

Answer 1

keeping in mind that perpendicular lines have negative reciprocal slopes, let's find what's the slope of y=-3x+7 anyway, wait just a second! y=-3x+7 is already in slope-intercept form
`\bf y=\stackrel{slope}{-3}x+7`.

and since that's the slope of that equation, a perpendicular line's will be

so we're really looking for the equation of a line whose slope is 1/3 and runs through -2,0,

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